How PFBC surveys lakes, and how to read a biologist report

PA Lake Fishing Almanac · reviewed Oct 4, 2026 against the 2026 Fishing Summary

Who does the surveys. PFBC's fisheries biologists work out of area offices; the agency publishes their reports on its Biologist Reports pages, one page per area (Areas 1–8 cover inland waters). The pages note: “Additional reports are available upon request.” (PFBC Biologist Reports, Area 1 page, retrieved Oct 4, 2026.)

The three main tools

As PFBC's own reports describe them:

• Electrofishing. Crews sample from a boat, often at night and along the shoreline, then measure the fish and release them. Examples: at Piney Reservoir, “During the night of May 15th, boat electrofishing was conducted at three sites.” and “All captured Walleye were measured for total length and released.” (PFBC report, Piney Reservoir 2016, p. 2.) At Northmoreland Lake the survey used “electrofishing runs covering the entire shoreline.” (2012, p. 1.)
• Trap nets. Set overnight, often in spring, mainly for panfish. PFBC: “Pennsylvania style trap nets are typically used to assess panfish populations in lakes throughout the state” (PFBC report, Pine Township Park Pond 2012, p. 2). Example: at Tuscarora Lake, “trap nets were set daily in water depths ranging from 4 to 19 feet and allowed to fish overnight (approximately 22 hours).” (2014, p. 2.)
• Gill nets. Used in some reports for open-water species. Examples: at Mahoning Creek Lake, “gill nets were set in water depths ranging from 10 to 50 feet deep and were fished overnight (approximately 24 hours).” (2018, p. 2.) At Hammond Lake, “Gill nets were fished concurrently with the trap nets to specifically target hybrid Striped Bass.” (2024, p. 5.)
• The same Pine Township report notes that “night electrofishing is often used in small impoundments where trap netting may not be feasible.” (p. 2.)

Why the gear matters

Each gear catches some fish better than others, so a report is about what that gear caught. At Colver Reservoir, biologists used “8 trap net sets to assess the panfish populations” and returned in May for night electrofishing “to assess the Largemouth Bass population”; the same report notes water temperatures “were too warm to adequately sample the Walleye population.” (PFBC report, Colver Reservoir 2017, p. 1.)

The numbers you'll see

• Number caught and size range — how many of each species, smallest to largest.
• Catch per hour (CPUE) — fish per hour of electrofishing or per net-night. It compares effort over time; it is not a count of the fish in the lake. Piney Reservoir: “The relative abundance was determined using catch per hour of electrofishing effort.” (2016, p. 2.)
• Percent over a length — e.g. the share of bass over 12 or 15 inches.
• Management criteria — some reports compare results with a PFBC plan. Sylvan Lake: “These catch rates exceeded the minimum criteria that the new plan defines for a quality walleye population, so stocking will continue.” (PFBC report, Sylvan Lake 2012, p. 1.)

How this site shows a report

For each lake we summarize the latest two reports PFBC lists: survey month and year, how old it is, the gear, 2–6 short findings in our words, at most three quotes of 25 words or fewer, and a citation with page number linking to PFBC's PDF. A program checked every number and species name against the cited page. Reports more than 10 years old carry the label “Historical survey”. We never rate a lake.

One survey is a snapshot

Weather, water temperature, season and gear all shape a catch. A survey describes those nets on those days.

Questions

Sources: PFBC Biologist Reports ↗ (area pages, retrieved Oct 4, 2026) and the PFBC reports cited above.